You have to train yourself to do it. For example, while you are awake you have to test your reality to see if you ARE awake. You can try reading something near you ( preferably a sentence ) look away and then look back and see if it reads the same. IF it does , you are awake. If you are dreaming it may mean the same thing but the words will be different. You have to do this repeatedly all day. There are other ways to check as well. Check this link out ( found on Fanpop in Dreams )
Scroll down to view the 6 basic steps )
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